Lock nut and method of making



Patented Sept. 15, 1936 UNITED STATES PATENT OFFICE LUCK NUT AND METHOD OF William E. Sharp, deceased, late of Chicago, Ill.,

by Minnie E. Sharp, executrix, Chicago,

Original application May 25, 1929, Serial No. 365,918. Divided and this application July 6, 1936, Serial N0. 89,214

18 Claims. (Cl. 10-86) n This application is a division of application I Figureisafurther enlarged fragmentary sec- Serial No. 365,918, filed by my testator, William tional view illustrating more clearly a typical E. Sharp, on May 25, 1929. l' distortion of nut threads in accordance with the This invention relates to lock nuts and, more invention. particularly, to an improved nut of the char- Figures 5, 6, and 7 are perspective views corre- 5 acter which is readily applied to an. associated sponding to Figure 1 but showing other embodibolt, but which binds thereon for a few of' the ments of the invention. outermost threads. Referring tothe drawing in detail, like parts The principal object of the invention, generally being designated by like reference characters,

considered, is to provide a threaded nut with a. and first considering the embodiment of the in- 10 portionwhich has been compressed into the body vention illustrated in Figures l, 2 and 3, there thereof to push the adjacent threads downwardis shown a nut I of hexagonal form, although it ly and toward the center of the nut, causing them willv be obvious that a blank of square or other to be tilted or partially rolled over, whereby they form may be used, if desired Seid nut is PrO- will bind upon an associated bolt. vided with a bolt hole 2, and from one face, l5

Another object of the invention is to provide preferably the upper or outermost face 3 is a proa lock nut involving a threaded nut in which a, jection 4. In the present embodiment of the proportion thereof `slightly beyond the root of the jection is annular and preferably concentric with threads of said nut is compressed into the body the bolt hole 2, the inner diameter of said DTO- thereof to squeeze the roots of the adjacent jection preferably corresponding with, or beine 2o threads inwardly, reduce the distance between slightly greater than, the I'OOt dihmeter 0f the adjacent sides of adjacent threads at the roots threads 5 Which are applied t0 the blank at the thereof, and cause them to bind intron an assobolt hole Y2 to produce the nut or threaded unciated bolt of the proper size so that the nut will finished 106k nllt- AlthOllgh the annuler lIJIO'- be securely held thereon without, however, damjection 4 is ShOEVn as being rectangular 0r Bp- 25. aging the threads on said b01t proximately square in cross section, it is obvious A` further object of the invention is to provide that the invention is not limited to this construca processor method of forming lock nuts involvtien. Y lng applying pressure to force a portion of one In Figure 3 there is ShOWn 2 hut embodying 3o face of a threaded nut partly into the body therethe invention and e bolt Whieh was inserted subao of to cause the metal adjacent thereto to now sequent to applying the looking properties to the downwardly and slightly decrease the distance nlllt The d Ot and dash. lines in this fleure, deS- between adjacent threads at their roots adjacent ignated by the reference character 4, indicate the said face of the blank, projection or upstanding collar before it was de- Other objects and advantages of the invention fieeted 0r Compressed into the nut t0 the extent 35 relating to the particular arrangement and eonindicated by the solid lines 4. This deflection struction of the various parts will become apparof the collar causes a ow of metal into the body ent as the description proceeds. of the blank, and because said collar is nearer the Referring to the drawing illustrating the 1nroots of the threads than the outer periphery of vention, the scope whereof is definedl by the apthe blank, the. main result 0f the 'deecton is t0 4 0 pended claims: cause the metal adjacent the outermost or top- Fgure 1 is a perspective view of one form of mest threads t0 110W inwardly and slightly f nut before the threads thereof have been distortsqueeze 0r contract the threads especially -at the ed in accordance with the invention. roots. n y Figure 2 is a, vertical Seotionej view through a; The crests of said threads, however, are nat- 45 pair of oppositely disposed flat sides of a nut urallyforced inward with the root portions, which such as shown inFigure 1. causes a tilting or partial rolling over of such Figure 3 isa fragmentary sectionalview, cor.. threads and a contraction in' diameter of the responding to Figure 2, on an enlarged scale and nut, so that when the nut l is screwed on the showing the form of the nut after the projection bolt s, it Will go thereOn es en Ordinary nut until 5o or collar has Vbeen compressed into the body of the last few threads, adjacent the outer or topthe blank to give-it the desired locking properties, most face, reach the outer threads on the bolt, a portion of an associated bolt being shown as when the threads on said nut will bind upon the applied to the nut after said nut has been given bolt threads, particularly Athe outer edge or top the desired locking properties. of the outermost engaged boltthread, and lock 55 to .the'desired extent. 0n account of the thread distortion being slight, the desired locking action is secured without resulting in appreciable permanent deformation of the threads of the bolt to which it is applied. y

Figure 4 is an enlarged diagrammatic viewl representing, in an exaggerated way, a typical thread distortion due to compressing the collar 4 into the body of the nut to the position designated by the reference character 4', the distortved nut section being superimposed over the undistorted section with the top faces of said sections in registry, in order to most clearly show the generalcharacter of the thread distortion under normal conditions. Y On account of the collar 4 being quite near the roots of the threads 5, the metal of said collar vwhich is pushed into the body of the nut l, goes diagonally downward and inward crowding the root portion between the two top threads from the position designated per root portion, a typical action of such threads is a tilting over such as is illustrated in this `figure. The relative distortion of the upper nut threads, as compared with the receiving valleys between associated bolt threads, causes a bend-l ing of thread crests and a corresponding locking action when the bolt is screwed in place. On account of the crowding of the root,'as indicated at 1', there is a'tendency-for the root portion between the top thread of the nut and that thread immediately below it, to bind upon the crest por- -tion I of the top thread I`l of the bolt 6, a

fragmentary portion only of which is shown. `".l'he binding action of the next to the top nut thread on the engaged bolt thread is satisfactory but usually different from the binding action illustrated, because it 1s generany tilted and .distorted blank I which is square rather than hexagonal,A

to Ia dilerent extent than the top thread. j Referring now to the embodiment of the invention illustrated vin Figure 5, there is shown a nut although as'will be understood, the same may be formed hexagonal or any other desired form within the spirit and scope of the invention.A Instead of using an annular projection as in the rst embodiment,- there is employed a plurality of outstanding projections 4n which may involve two parallel rows of projections, the inner edges of said rows being disposed adjacent or slightly outwardly of the roots of the threads at the bolt hole 2'L of vthe nut. If desired, the projec- "tions may be elongated and formed as two parallel relatively long extensions, as shown at 4" A'Iii on the-nut Ib in Figure 6, rather than two parallel rows of short extensions.

Referring now to the embodiment of the invention illustrated in Figure '1, there is shown a nut I threaded at 5 like the nut of Figures `5v and 6. Said'nut is illustrated as square like the nuts'of Figures 5 and 6, although itwlll be understood that it may, if desired, be formed hexagonal asshowninFigureslandf. Insteadofhaving projections from the top face thereof, as in the previous embodiment, said nut l may be formed plane faced and have the top face thereof depressed along parallel grooves, as indicated at 4, said grooves being positioned adjacent the roots of the threads 5 and preferably disposed slightly outwardly thereof like the projections 4b in Fig'- ure 6. The effect of compressing the metal of the nut Ic to produce the grooves 4c, disposed like the ridges or extensions 4b of Figure 6, is substantially identical with that produced in connection with the formation of the lock nut shown in Figure 6, in that the metal adiacent the topmost threads is caused to flow inwardly and slightly squeeze said threads more lparticularly at the roots thereof, thereby reducing the distance between adjacent threads slightly to cause said threads to bind upon a correspondingly threaded bolt on both sides of the threads thereof; particularly at the tops of said threads.

On account of the position at which the gefleeting $001 is applied to the standard or commercial form of nut to .produce the` pressure grooves 4c, as shown in Figure 7, the metal' of the nut flows both inwardly toward the axis of the nut and along the bolt hole parallel to the axis in the direction of movement of the die. 'I'he fact that the tool is applied nearer the bolt hole than the outer surfaces of the nut causes practically all of the lateral movement to be inward rather than outward, giving a resultant diagonal movement to the deflected metal. As a result of the metal movement, the threads are given a slight wave, and the hole is-slightly flattened at the opposite sides adjacent the grooves 4. The waved portions of the threads, that is, the portions of the surface of the hole which are distorted, taper from the upper surface of the nut toward the original surface of cylindrical form on which the threads are applied. Not only are the threads waved and flattened by the pressing operation, but there is likewise a rolling-over or angular displacement of the threads themselves, which may be referred to as a protrusion effect, whereby the rolled-over threads vll be caused to grip the threads of an associated bolt, so that accidental removal of the nut is avoided. When the bolt is screwed into the nut, there is a gradual locking effect due both to the wave of the threads and the protrusion of 'the parts,but

neither the thread wave nor lthe flattenedeil'ect is sufficient to fdamage the threads of the bolt.

Instead of making the nut lc as a plane faced nut, it will, of course, be. obvious that, if desired,

it may be made with grooves 4c thereon-initially and subsequently the metal maybecompressed in said grooves.

The .foregoing discloses a lock nut and process of makingthe same in which some of the threads of an ordinary or standard nut are distorted to provides. locking action. One form of the invention involves the formatlon, on one face of the nut, of 'an annular projection concentric with the bolt hole and having an inner diameter corresponding with, or being slightly greater than, the root diameter of the nut threads, said projection being partly compressed into the body of the nut to modify the threads adjacent thereto, so that they will bind upon an f bolt when the! nut is applied thereto. In--this form the metal of the nut is crowded, causing a slight contraction of the diameter o! the lint adjacent the top face, or that which carries thefannular projection,`as well as involving 'a tilting of the nut threads adjacentsaid contracted portion.

l In the form of the invention in whichthe metal is distorted or forced into the nut en two opposite elongated or flattened 'at opposite sides, and the threads are waved or displaced longitudinally adjacent said parallel deflected portions, as well as being tilted or partially rolled over, as compared with the thread-portions between said parallel deflected portions, so that such lock nuts do not give exactly the same locking action as those in which the metal is distorted around the full periphery. However, in all forms of the invention the distortion is at or adjacent the root threads, so that the metal, at the positions where the distortion takes place, is caused to move both longitudinally and radially inward of the nut, so that the resultant displacement =is diagonal toward the nut axis.

Although preferred forms of the invention have been disclosed, it will be understood that modications may be made therein within the spirit and scope of the appended claims.

What is claimed is:

xl. The process of forming a lock nut comprising making a blank with an upright sidedpro jection extending from one face thereof and with its inner side spaced from the bolt hole, threading said blank and applying pressure to said projection to cause the metal adjacent the roots of the threads to flow inwardly and slightly distort said threads.

2. The process of forming a lock nut comprising making a threaded blank with an approximately rectangular projection upstanding from one face thereof adjacent the roots of the threads and with its inner side spaced from the bolt hole, applying pressure to said projection to force the metal thereof into said blank and cause the threads adjacent thereto to be distorted, whereby they will bind upon anassociated bolt.

3. The process of forming a lock nut compri.,- lng making a blank with an annular collar on one face thereof, the inner edge of said collar being spaced from the bolt hole, threading said blank to form a nut and applying pressure to said collar to cause the metal adjacent thereto to ow inwardly, causing the root portions of threads adjacent said collar to be crowded.

4. rI'he process of forming a lock nut compris-` ing making a threaded blank with an annular collar upstanding from the top face thereof, said collar being disposed so that its inside diameter is slightly larger than the diameter of the nut at the roots of the threads, and applying pressure to force the collar partly into the body of the nut and cause the threads adjacent the top face of the nut to be distorted adjacent theAroots thereof, whereby they will bind upon corresponding threads, of an associated bolt, adjacent the top thereof.

5. A lock nut comprising a threaded blank with a distorted portion on one face thereof, said portion having its inner'edge spaced slightly outward from the roots of the threads and having been compressed to cause the threads adjacent thereto to be crowded especially adjacent the roots, whereby said threads will bind upon an associated bolt. i

6. A lock nut comprising a threaded blank with an upstanding projection on its top face, said projection being disposed adjacent and outwardly of the roots of the threads and being compressed into the body of the nut so that the threads adjacent thereto will contract slightly especially-adjacent the roots thereof to cause them to bind upon an associated bolt.

'7.-A lock nut comprising a threaded blank with an annular collar on one face thereof, said collar having an inner diameter greater than the thread root diameter and having been compressed to cause the threads adjacent thereto to be slightly contracted and crowded at the roots.

8. A lock nut comprising a threaded blank with an annular upstanding collar on the top face thereof, the inner diameter of saidV collar being slightly greater than the diameter at the roots of the threads, said collar being concentric with the threads and slightly compressed into the body of the nut so that said threads adjacent the top face of the nut are contracted slightly and have their root portions crowded together, causing them to bind upon an associated bolt.

9. The process of forming a lock nut comprising making a threaded blank with an annular collar substantially rectangular in section upstanding from the top face thereof, said collar having'an inside diameter slightly larger than the thread root diameter and an outside diameter less than the outside dimensions of the nut, and applying pressure to said collar to force it partly into the body of the nut and cause the threads adjacent the top face thereof to be contracted at the roots whereby they will bind the engaging portions of threads upon an associated bolt.

10. A lock nut formed with an annular upstanding collar substantially rectangular in section,

with its inner diameter slightly greater than the thread root diameter, concentric with said threads,

I a'nd slightly compressed into the body of the nut so that the threads `adjacent the top face thereofv are contracted, especially at the root, iso-cause them to bind upon an associated bolt.

11. A lock nut in which the threads adjacent one face thereof are slightly contracted, especially adjacent the roots, whereby they will bind the outermost portions of corresponding threads on an associated bolt.

12. The method of converting a standard nut into a lock nut which comprises pressure-indenting an end portion to wave the thread adjacent thereto anddisplace the metal at the periphery Awavy thread. Y

of the' hole both inwardly toward the axis of the 15. A lock nut having a partially rolled over wavy thread and the hole provided with a flattened portion where the threads are waved.

16. A lock nut formed from aV standard nut and having a'portion of the metal at the periphery of the hole pressed -longitudinally and laterally of the nut and the thread waved.

17. A lock nut formed from a standard nut and having a portion of the metalat the periphery of the bolt hole pressed longitudinally and laterally of the nut and the thread waved and partially.

rolled over.

18. The method of converting an ordinary tions of the threads of the nut are tilted so that threaded metal nut into a lock-nut, which comprises displacing' an annular portion of the metal concentric with the bolt hole into said nut, said annular portionbeingso near the roots of the nut threads that 'the metal defining the periphery of the hole isdisplaced inwardly toward the axis of the nut as well. as longitudinally, whereby po'rthey will grip engaging portions of an associated bolt.

Ezecutz of theEsta ased.

MINNIE E. SHARP, 

